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>CHECKPOINT</H1
><DIV
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><A
NAME="AEN63319"
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><H2
>Name</H2
>CHECKPOINT&nbsp;--&nbsp;force a transaction log checkpoint</DIV
><DIV
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><A
NAME="AEN63324"
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><H2
>Synopsis</H2
><PRE
CLASS="SYNOPSIS"
>CHECKPOINT</PRE
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><A
NAME="AEN63326"
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><H2
>Description</H2
><P
>   Write-Ahead Logging (WAL) puts a checkpoint in the transaction log
   every so often. (To adjust the automatic checkpoint interval, see
   the run-time configuration options <A
HREF="runtime-config-wal.html#GUC-CHECKPOINT-SEGMENTS"
>checkpoint_segments</A
>
   and <A
HREF="runtime-config-wal.html#GUC-CHECKPOINT-TIMEOUT"
>checkpoint_timeout</A
>.)  The
   <TT
CLASS="COMMAND"
>CHECKPOINT</TT
> command forces an immediate
   checkpoint when the command is issued, without waiting for a
   scheduled checkpoint.
  </P
><P
>   A checkpoint is a point in the transaction log sequence at which
   all data files have been updated to reflect the information in the
   log.  All data files will be flushed to disk.  Refer to
   <A
HREF="wal.html"
>Chapter 29</A
> for more information about the WAL system.
  </P
><P
>   If executed during recovery, the <TT
CLASS="COMMAND"
>CHECKPOINT</TT
> command
   will force a restartpoint rather than writing a new checkpoint.
  </P
><P
>   Only superusers can call <TT
CLASS="COMMAND"
>CHECKPOINT</TT
>.  The command is
   not intended for use during normal operation.
  </P
></DIV
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><A
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></A
><H2
>Compatibility</H2
><P
>   The <TT
CLASS="COMMAND"
>CHECKPOINT</TT
> command is a
   <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
> language extension.
  </P
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